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1.
J Xray Sci Technol ; 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33044223

RESUMO

BACKGROUND: Radiation risk from computed tomography (CT) is always an issue for patients, especially those in clinical conditions in which repeated CT scanning is required. For patients undergoing repeated CT scanning, a low-dose protocol, such as sparse scanning, is often used, and consequently, an advanced reconstruction algorithm is also needed. OBJECTIVE: To develop a novel algorithm used for sparse-view CT reconstruction associated with the prior image. METHODS: A low-dose CT reconstruction method based on prior information of normal-dose image (PI-NDI) involving a transformed model for attenuation coefficients of the object to be reconstructed and prior information application in the forward-projection process was used to reconstruct CT images from sparse-view projection data. A digital extended cardiac-torso (XCAT) ventral phantom and a diagnostic head phantom were employed to evaluate the performance of the proposed PI-NDI method. The root-mean-square error (RMSE), peak signal-to-noise ratio (PSNR) and mean percent absolute error (MPAE) of the reconstructed images were measured for quantitative evaluation of the proposed PI-NDI method. RESULTS: The reconstructed images with sparse-view projection data via the proposed PI-NDI method have higher quality by visual inspection than that via the compared methods. In terms of quantitative evaluations, the RMSE measured on the images reconstructed by the PI-NDI method with sparse projection data is comparable to that by MLEM-TV, PWLS-TV and PWLS-PICCS with fully sampled projection data. When the projection data are very sparse, images reconstructed by the PI-NDI method have higher PSNR values and lower MPAE values than those from the compared algorithms. CONCLUSIONS: This study presents a new low-dose CT reconstruction method based on prior information of normal-dose image (PI-NDI) for sparse-view CT image reconstruction. The experimental results validate that the new method has superior performance over other state-of-art methods.

2.
Bioorg Chem ; 105: 104332, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33038553

RESUMO

Four new diterpenoids (1-4), three new triterpenoids (12-14), and seven known diterpenoids (5-11) were obtained from an aqueous EtOH extract of the aerial parts of Triadica rotundifolia. The structures of new compounds were determined by spectroscopic techniques. Their absolute configurations were verified via single-crystal X-ray diffraction data, Mo2(OAc)4 induced electronic circular dichroism (ECD), and ECD calculations. The antineuroinflammatory effects of the isolates were assessed by inhibiting NO production in LPS-induced BV-2 microglial cells. Compared with the positive control minocycline (IC50 = 16.1 µM), compounds 3, 8, 11 showed moderate inhibitory activities with IC50 values of 35.9, 17.0, 31.5 µM, respectively.

4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1485-1488, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018272

RESUMO

The susceptibility-based positive contrast MR technique was applied to estimate arbitrary magnetic susceptibility distributions of the metallic devices using a kernel deconvolution algorithm with a regularized L-1 minimization. Previously, the first-order primal-dual (PD) algorithm could provide a faster reconstruction time to solve the L-1 minimization, compared with other methods. Here, we propose to accelerate the PD algorithm of the positive contrast image using the multi-core multi-thread feature of graphics processor units (GPUs). The some experimental results showed that the GPU-based PD algorithm could achieve comparable accuracy of the metallic interventional devices in positive contrast imaging with less computational time. And the GPU-based PD approach was 4~15 times faster than the previous CPU-based scheme.Clinical Relevance-This can estimate arbitrary magnetic susceptibility distributions of the metallic devices with the processing efficacy of 4~15 times faster than before.

5.
J Pharm Biomed Anal ; 191: 113587, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32892084

RESUMO

Methylation of lysine by histone methyltransferases can be reversed by lysine demethylases (KDMs). Different KDMs have distinct oncogenic functions based on their cellular localization, stimulating cancer cell proliferation, reducing the expression of tumor suppressors, and/or promoting the development of drug resistance. JIB-04 is a small molecule that pan-selectively inhibits KDMs, showing maximal inhibitory activity against KDM5A, and as secondary targets, KDM4D/4B/4A/6B/4C. Recently, it was found that JIB-04 also potently and selectively blocks HIV-1 Tat expression, transactivation, and virus replication in T cell lines via the inhibition of a new target, serine hydroxymethyltransferase 2. Pharmacokinetic characterization and an analytical method for the quantification of JIB-04 are necessary for the further development of this small molecule. Herein, a sensitive, specific, fast and reliable UHPLC-MS/MS method for the quantification of JIB-04 in rat plasma samples was developed and fully validated using a SCIEX 6500+ triple QUAD LC-MS system equipped with an ExionLC UHPLC unit. The chromatographic separation was achieved on a reverse phase ACE Excel 2 Super C18 column with a flow rate of 0.5 mL/min under gradient elution. The calibration curves were linear (r2 > 0.999) over concentrations from 0.5 to 1000 ng/mL. The accuracy (RE%) was between -7.4% and 3.7%, and the precision (CV%) was 10.2% or less. The stability data showed that no significant degradation occurred under the experimental conditions. This method was successfully applied to the pharmacokinetic study of JIB-04 in rat plasma after intravenous and oral administration and the oral bioavailability of JIB-04 was found to be 44.4%.

6.
Eur J Radiol ; 131: 109219, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32905953

RESUMO

PURPOSE: To develop a radiomics signature using diffusion-weighted imaging (DWI) for predicting progression-free survival (PFS) in muscle-invasive bladder cancer (MIBC) patients and to assess its incremental value over traditional staging system. METHOD: 210 MIBC patients undergoing preoperative DWI were enrolled. A radiomics signature was built using LASSO model. A radiomics nomogram was generated to assess the incremental value of the radiomics signature over existing risk factors in PFS estimation in terms of calibration, discrimination, reclassification and clinical usefulness. Kaplan-Meier analysis was used to assess the association of the radiomics signature with PFS. C-index was used as a discrimination measure. Net reclassification improvement (NRI) was calculated to evaluate the usefulness improvement added by the radiomics signature. Decision curve analysis was performed to evaluate the clinical usefulness of the nomograms. RESULTS: The radiomics signature was significantly associated with PFS (log-rank P = 0.0073) and was independent with clinicopathological factors (P = 0.0004). The radiomics nomogram achieved better performance in PFS prediction (C-index: 0.702, 95 % confidence interval [CI]: 0.602, 0.802) than either clinicopathological nomogram (C-index: 0.682, 95 % CI: 0.575, 0.788) or radiomics signature (C-index: 0.612, 95 % CI: 0.493, 0.731), and achieved better calibration and classification (NRI: 0.226, 95 % CI: 0.016, 0.415, P = 0.038). Decision curve analysis demonstrated the better clinical usefulness of the radiomics nomogram. CONCLUSIONS: The DWI-based radiomics signature was an independent predictor of PFS in MIBC patients. Combining the radiomics signature, clinical staging and other clinicopathological factors achieved better performance in individual PFS prediction.

7.
Ecotoxicol Environ Saf ; 207: 111258, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32971319

RESUMO

This study investigated whether bioaugmentation improves sulfamethoxazole (SMX) degradation and nitrogen removal in the Moving Bed Biofilm Reactor (MBBR) system. The effects of the C/N ratio on SMX degradation and nitrogen removal were also evaluated. Using MBBR system operation experiments, the bioaugmented reactor was found to perform more effectively than the non-bioaugmentation reactor, with the highest SMX, nitrate-N, and ammonia-N removal efficiencies of 80.49, 94.70, and 96.09%, respectively. The changes in the sulfonamide resistance genes and bacterial communities were detected at various operating conditions. The results indicate that the diversity of the bacterial communities and the abundance of resistance genes were markedly influenced by bioaugmentation and the C/N ratio, with Achromobacter among the dominant genera in the MBBR system. The bio-toxicity of samples, calculated as the inhibition percentage (IP) toward Escherichia coli, was found to decrease to non-toxic ranges after treatment.

8.
Mol Neurobiol ; 57(12): 5276-5285, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32870492

RESUMO

Neuregulin 1 (NRG1)-induced activation of ErbB4 in parvalbumin (PV) inhibitory interneurons is reported to serve as a critical endogenous negative-feedback mechanism to repress brain epileptogenesis. Here, we investigated the seizure susceptibility and the role of NRG1-ErbB4 signaling in PV interneurons in the suppression of epileptic seizures for rats subject to early life hypoxia. Neonatal postnatal day 5 (P5) rats were exposed to intermittent hypoxia (IH) or control (CON) room air for 10 days. In the prefrontal cortex (PFC) of P54 rats, we determined the impact of neonatal IH exposures on the expression of PV, NRG1, ErbB4, and phosphorylated ErbB4 (p-ErbB4) during the seizure induction. Seizure susceptibility tests with the common convulsant agent pentylenetetrazole (PEN) at P54 revealed that rats subject to neonatal hypoxia exposure developed faster and more serious epileptic seizures. Neonatal IH exposures (1) decreased the number of PV cells in the PFC of P54 rats; (2) interrupted the expression of NRG1 gene; and (3) altered the activity of NRG1 on PV interneurons in the PFC after the seizure induction. Intracerebroventricular delivery of exogenous NRG1 before seizure induction by PEN significantly reduced the seizure susceptibility for neonatal IH-exposed rats. The ErbB4 inhibitor AG1478 inhibited the exogenous NRG1's effects on seizure susceptibility. Environmental enrichment (EE) rescued the abovementioned pathophysiological alterations and significantly attenuated the epileptic seizures after the seizure induction for neonatal IH-exposed rats. Our study indicated early life hypoxia exposure might increase the seizure susceptibility for rats and contribute to pathophysiological dysfunction of NRG1-ErbB4 signaling in PV interneurons in the suppression of epileptic seizures. EE might attenuate the increased seizure susceptibility for neonatal IH-exposed rats through rescuing pathophysiological alterations of NRG1-ErbB4 signaling in PV interneurons.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32909077

RESUMO

BACKGROUND: The clinical predictors and biological mechanisms for localized prostate cancer (PCa) outcomes remain mostly unknown. We aim to evaluate the role of serum immune-checkpoint-related (ICK) proteins and genetic variations in predicting outcomes of localized PCa. METHODS: We profiled the serum levels of 14 ICK-related proteins (BTLA, GITR, HVEM, IDO, LAG-3, PD-1, PD-L1, PD-L2, Tim-3, CD28, CD80, 4-1BB, CD27, and CTLA-4) in 190 patients with localized PCa. The genotypes of 97 single nucleotide polymorphisms (SNPs) from 19 ICK-related genes were analyzed in an extended population (N = 1762). Meta-data from ArrayExpress and TCGA was employed to validate and to probe functional data. Patients were enrolled and tumor aggressiveness, biochemical recurrence (BCR), and progression information were obtained. Statistical analyses were performed analyzing associations between serum biomarkers, genotypes, mRNA and outcomes. RESULTS: We showed that serum (s)BTLA and sTIM3 levels were associated with PCa aggressiveness (P < 0.05). sCD28, sCD80, sCTLA4, sGITR, sHVEM and sIDO correlated with both BCR and progression risks (all P < 0.05). We further identified ICK variants were significantly associated with aggressiveness, BCR and progression. Among them, 4 SNPs located in CD80 (rs7628626, rs12695388, rs491407, rs6804441) were not only associated with BCR and progression risk, but also correlated with sCD80 level (P < 0.01). rs491407 was further validated in an independent cohort. The CD80 mRNA expression was associated with BCR (HR, 1.85, 95% CI 1.06-3.22, P = 0.03) in meta-analysis of validation cohorts. CONCLUSION: We highlight the prognostic value of serum ICK-related proteins for predicting aggressiveness, BCR and progression of PCa. The genetic variations and mRNA expression in CD80 could be predictors and potential targets of localized PCa.

10.
IEEE Trans Med Imaging ; PP2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32886608

RESUMO

The Wave Controlled Aliasing In Parallel Imaging (Wave-CAIPI) technique manifests great potential to highly accelerate three-dimensional (3D) balanced steady-state free precession (bSSFP) through substantially reducing the geometric factor (g-factor) and aliasing artifacts of image reconstruction. However, severe banding artifacts appear in bSSFP imaging due to unbalanced gradients with nonzero 0th moment applied by the conventional Wave-CAIPI technique. In this study, we propose a 3D Wave-bSSFP scheme that adopts truncated wave gradients with zero 0th moment to avoid introducing additional banding artifacts and to maintain the advantages of wave encoding. The simulation results indicate that the number of wave cycles that are truncated and different options of applying wave gradients affect both the g-factor reduction and image quality, but the influence is limited. In phantom experiments, the proposed technique shows similar acceleration performance as the conventional Wave-CAIPI technique and effectively eliminates its introduced banding artifacts. Additionally, Wave-bSSFP obtains up to 12× retrospective acceleration at 0.8 mm isotropic resolution in in vivo 3D brain experiments and is superior to the state-of-the-art Controlled Aliasing In Parallel Imaging Results IN Higher Acceleration (CAIPIRINHA) technique, according to both visual validation and quantitative analysis. Moreover, in vivo 3D spine and abdomen imaging demonstrate the potential clinical applications of Wave-bSSFP with fast acquisition speed, improved isotropic resolution and fine image quality.

11.
J Xray Sci Technol ; 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32925159

RESUMO

Breast cancer is the most frequently diagnosed cancer in women worldwide. Digital breast tomosynthesis (DBT), which is based on limited-angle tomography, was developed to solve tissue overlapping problems associated with traditional breast mammography. However, due to the problems associated with tube movement during the process of data acquisition, stationary DBT (s-DBT) was developed to allow the X-ray source array to stay stationary during the DBT scanning process. In this work, we evaluate four widely used and investigated DBT image reconstruction algorithms, including the commercial Feldkamp-Davis-Kress algorithm (FBP), the simultaneous iterative reconstruction technique (SIRT), the simultaneous algebraic reconstruction technique (SART) and the total variation regularized SART (SART-TV) for an s-DBT imaging system that we set up in our own laboratory for studies using a semi-elliptical digital phantom and a rubber breast phantom to determine the most superior algorithm for s-DBT image reconstruction among the four algorithms. Several quantitative indexes for image quality assessment, including the peak signal-noise ratio (PSNR), the root mean square error (RMSE) and the structural similarity (SSIM), are used to determine the best algorithm for the imaging system that we set up. Image resolutions are measured via the calculation of the contrast-to-noise ratio (CNR) and artefact spread function (ASF). The experimental results show that the SART-TV algorithm gives reconstructed images with the highest PSNR and SSIM values and the lowest RMSE values in terms of image accuracy and similarity, along with the highest CNR values calculated for the selected features and the best ASF curves in terms of image resolution in the horizontal and vertical directions. Thus, the SART-TV algorithm is proven to be the best algorithm for use in s-DBT image reconstruction for the specific imaging task in our study.

13.
Phys Med Biol ; 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32992302

RESUMO

In this work, a small animal PET scanner named SIAT aPET was developed using dual-ended readout depth encoding detectors to simultaneously achieve high spatial resolution and high sensitivity. The scanner consists of 4 detector rings with 12 detector modules per ring; the ring diameter is 111 mm and the axial field of view is 105.6 mm. The images are reconstructed using an ordered subset expectation maximization (OSEM) algorithm. The spatial resolution of the scanner was measured by using a 22Na point source at the center axial field of view with different radial offsets. The sensitivity of the scanner was measured at center axis of the scanner with different axial positions. The count rate performance of the system was evaluated by scanning mouse-sized and rat-sized phantoms. An ultra-micro hot-rods phantom and two mice injected with 18F-NaF and 18F-FDG were scanned on the scanner. An average DOI resolution of 1.96 mm, energy resolution of 19.1% and timing resolution of 1.20 ns were obtained for the detector. Average spatial resolutions of 0.82 mm and 1.16 mm were obtained up to a distance of 30 mm radially from the center of the field of view when reconstructing a point source in 1% and 10% warm backgrounds, respectively, using OSEM reconstruction with 16 subsets and 10 iterations. Sensitivities of 16.0% and 11.9% were achieved at center of the scanner for energy windows of 250-750 keV and 350-750 keV respectively. Peak noise equivalent count rates of 324 kcps and 144 kcps were obtained at an activity of 26.4 MBq for the mouse-sized and rat-sized phantoms. Rods of 1.0 mm diameter can be visually resolved from the image of the ultra-micro hot-rods phantom. The capability of the scanner was demonstrated by high quality in-vivo mouse images.

14.
Bioresour Technol ; 319: 124149, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32979596

RESUMO

This study investigated the effect of thermal pretreatment (TP) on the lignocellulose degradation and humification during dairy manure composting and the underlying microbial mechanism. The results showed that TP accelerated temperature rise and elevated composting temperature by increasing 26% initial content of simple organics. The degradation of cellulose, hemicellulose and lignin was 78, 10 and 109% higher in thermal pretreatment composting (TPC) than traditional composting (TC), respectively. Moreover, TP significantly improved the humification degree of composts, as indicated by 14 and 38% higher humus content and humification indexes in TPC, respectively. 16S rRNA sequencing showed that TP increased the relative abundance of thermophilic bacteria in TPC, of which Thermobifida, Planifilum, Truepera and Thermomonospora were potentially involved in lignocellulose biodegradation and humification. Canonical correspondence analysis revealed that TP changed the main factor determining the bacterial community evolution from dissolved organic carbon (DOC) in TC to temperature in TPC.

15.
J Agric Food Chem ; 68(41): 11421-11433, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32936614

RESUMO

The newly released Donghong kiwifruit is a promising commercial cultivar. The dynamic changes of major phenolic compounds (flavonols, flavanols, phenolic acids, and anthocyanins) during the representative stages of fruit development and ripening of the Donghong kiwifruit were determined by high-performance liquid chromatography. The corresponding time-course transcriptional changes were evaluated using the combined analysis of RNA-Seq and qRT-PCR. The most predominant phenolic compound in the Donghong kiwifruit was epicatechin. Cyanidin 3-O-[2-O-(ß-xylosyl)-ß-galactoside] and cyanidin 3-O-ß-galactoside were two essential anthocyanins detected. Candidate genes and pathways involved in phenolic compounds biosynthesis were highlighted. The structural genes (AcLDOX2, Ac5GGT1, and Ac5AT2) and the transcription factor (bHLH74-2) were strongly associated with anthocyanin biosynthesis. AcMYB4-1 may be a novel transcription factor that reduces anthocyanin accumulation. Results from the study may be a very useful supplement to current knowledge of molecular mechanisms to elucidate coloration in the red-fleshed kiwifruit and could help breeders modify the kiwifruit germplasm.

16.
J Am Chem Soc ; 142(34): 14432-14436, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32786737

RESUMO

We report herein a strategy to construct enantiopure inherently chiral macrocycles, ABCD-type heteracalix[4]aromatics, through a catalytic enantioselective intramolecular C-N bond forming reaction. A chiral ligand-palladium complex was found to efficiently induce the inherent chirality of molecules during the macrocyclization process with ee values up to >99%. The resulting ABCD-type heteracalix[4]aromatics displayed excellent and pH-triggered switchable electronic circular dichroism and circularly polarized luminescence properties.

17.
Sensors (Basel) ; 20(16)2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32824031

RESUMO

Vertical heterogeneity of the biochemical characteristics of crop canopy is important in diagnosing and monitoring nutrition, disease, and crop yield via remote sensing. However, the research on vertical isomerism was not comprehensive. Experiments were carried out from the two levels of simulation and verification to analyze the applicability of this recently development model. Effects of winter wheat on spectrum were studied when input different structure parameters (e.g., leaf area index (LAI)) and physicochemical parameters (e.g., chlorophyll content (Chla+b) and water content (Cw)) to the mSCOPE (Soil Canopy Observation, Photochemistry, and Energy fluxes) model. The maximum operating efficiency was 127.43, when the winter wheat was stratified into three layers. Meanwhile, the simulation results also proved that: the vertical profile of LAI had an influence on canopy reflectance in almost all bands; the vertical profile of Chla+b mainly affected the reflectivity of visible region; the vertical profile of Cw only affected the near-infrared reflectance. The verification results showed that the vegetation indexes (VIs) selected of different bands were strongly correlated with the parameters of the canopy. LAI, Chla+b and Cw affected VIs estimation related to LAI, Chla+b and Cw respectively. The Root Mean Square Error (RMSE) of the new-proposed NDVIgreen was the smallest, which was 0.05. Sensitivity analysis showed that the spectrum was more sensitive to changes in upper layer parameters, which verified the rationality of mSCOPE model in explaining the law that light penetration in vertical nonuniform canopy gradually decreases with the increase of layers.

18.
J Colloid Interface Sci ; 582(Pt A): 70-80, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32810691

RESUMO

In the study, we present a quick potassium hydroxide heat treatment approach to optimize the "melon" framework of graphite carbon nitride and modify the surface properties by functionalization of hydroxyl groups. The hydroxyl groups functionalized g-CN samples have been applied as bifunctional materials for efficient elimination of diquat dibromide herbicide through synergistic adsorption/photodegradation processes. The structural characterizations of the as-obtained samples, combined with the detailed diquat dibromide herbicide adsorption study, reveal that the surface hydroxyl groups are the active sites for the diquat dibromide adsorption, which account for the much enhanced saturation adsorption capacities of 159.3 mg g-1 at 25 °C and pH = 7 (more than 110 times improvement compared with pristine carbon nitride). Furthermore, the grafted surface hydroxyl groups and optimized planar structures endow the functionalized samples with the advantageous properties of efficient photoinduced charge transfer and separation, low interface resistance, and high photoresponse. Consequently, the deep mineralization of diquat dibromide herbicide was achieved over the bifunctional materials (total removal ratios were ~ 97.1% after 240 min visible-light irradiation). This work not only demonstrates the feasibility of hydroxyl groups functionalized graphite carbon nitride for elimination of herbicide pollutants but also offers new insights to better design efficient and durable materials for environmental remediation.

19.
Cell Death Dis ; 11(8): 615, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792479

RESUMO

Our group previously identified that the NOTCH1 Abruptex domain contains the most mutations in Chinese OSCC patients, including a hotspot mutation (C1133Y). FBXW7 is an E3 ubiquitin ligase that regulates a network of proteins, including NOTCH1, via degradation. In this study, we first described the co-localization of isoform specific FBXW7-FBXW7ß and NOTCH1C1133Y mutation in the same cytoplasmic sites. Gain- and loss-of-function assays were performed to examine the tumor suppressor role of FBXW7ß in the proliferation and invasion of OSCC cells. The co-expression of NOTCH1C1133Y and FBXW7ß significantly attenuated tumor growth. Meanwhile, FBXW7ß reversed the oncogenic phenotype and the activation of the AKT/ERK/NFκB pathway induced by NOTCH1C1133Y mutation. FBXW7ß downregulated the stability of NOTCH1C1133Y protein and promoted protein ubiquitination. This was the first time that we selected a NOTCH1 hotspot mutation detected in clinical samples and identified the function of FBXW7ß that mediated NOTCH1 mutation degradation in OSCC. The newly identified interaction between FBXW7ß and NOTCH1C1133Y protein provides new insights into the progression of OSCC, especially regarding Abruptex domain mutations, and represents a valuable target for OSCC therapy.

20.
IEEE Trans Biomed Eng ; PP2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32746069

RESUMO

OBJECTIVE: The purpose of this work is to investigate the feasibility of using deep convolutional neural network (CNN) to improve the image quality of a grating-based X-ray differential phase contrast imaging (XPCI) system. METHODS: In this work, a novel deep CNN based phase signal extraction and image noise suppression algorithm (named as XP-NET) is developed. The numerical phase phantom, the ex vivo biological specimen and the ACR breast phantom are evaluated via the numerical simulations and experimental studies, separately. Moreover, images are also evaluated under different low radiation levels to verify its dose reduction capability. RESULTS: Compared with the conventional analytical method, the novel XP-NET algorithm is able to reduce the bias of large DPC signals and hence increasing the DPC signal accuracy by more than 15%. Additionally, the XP-NET is able to reduce DPC image noise by about 50% for low dose DPC imaging tasks. CONCLUSION: This proposed novel end-to-end supervised XP-NET has a great potential to improve the DPC signal accuracy, reduce image noise, and preserve object details. SIGNIFICANCE: We demonstrate that the deep CNN technique provides a promising approach to improve the grating-based XPCI performance and its dose efficiency in future biomedical applications.

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